As the world reels following the tragic terrorist attacks in Paris, world leaders say they are determined to press on with the U.N. Climate Conference there, scheduled for the end of this month. But judging from past international climate agreements, attendance might not be worth the imposition.

There will be a new climate agreement. Last year’s U.N. climate show, in Lima, produced a requirement that countries that signed on to the 1992 Framework Convention on Climate Change produce an “Intended, Nationally Determined Contribution” of reductions in emissions of carbon dioxide long before Paris. So far, nations responsible for 91 percent of current global emissions have done so. That’s close enough to 100 percent to be able to claim a global agreement.

By having everyone provide their own plan (even if it’s not much of one), no one can complain that this supranational body is cramming anything down their throats, so that usual source of climate bickering won’t happen. And the plans are free to be meaningless.

Manhattan Institute scholar Oren Cass has shown that, in aggregate, the nations of the world have pledged to do nothing more than business as usual. Nations with maturing economies naturally see their emissions begin to level off. Those with developing economies will increase their emissions, but the amount they emit per capita, known as the emissions intensity, will eventually drop due to economies of scale.

China is one of those maturing economies. They have said they “intend” to start holding emissions constant “around 2030.” Between now and then, their emissions will rise by 50 to 100 percent. Experts at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory calculated four years ago that China’s emissions would peak around then. So the Chinese are doing nothing.

India says it will reduce its emissions per capita by 33 to 35 percent. Earlier this year, India’s own Centre for Policy Research concluded that this was the most likely outcome in the absence of any serious attempt to reduce emissions. In testimony to a House science panel this week, Oren Cass notes that this is about half of India’s intensity drop in recent years. In other words, India proposes to do something that is marginally less than nothing.

The U.S. is actually doing more than most countries. The Obama administration says it “intends to achieve” a total emissions reduction of 26 to 28 percent below 2005 values by 2025, with hope that it will go to 30 percent by 2030. This is less than what we proposed at the 2009 Copenhagen climate conference, the last serious stab at a climate treaty — which failed.

So the world’s largest emitter (China) and the third-largest one (India) aren’t doing anything, but we are, and it’s going to cost. Here’s one reason: Under Obama’s Clean Power Plan, substitution of natural gas for coal in electrical generation isn’t going to increase, even though it produces only half the carbon dioxide per kilowatt of electricity as coal. Instead, his EPA says power companies have to substitute unreliable, expensive “renewables,” mainly solar energy and wind. These are mighty expensive compared with new natural-gas power. And even the Clean Power Plan won’t meet our Paris target.

That’s going to be made up by mandating that the average passenger car and pickup truck get 55 miles per gallon by 2025. Even a Prius sedan doesn’t get that much in the real world, according to the true-mileage site fuel​ly​.com. Honda and Toyota’s clear reluctance to stay away from mega-battery cars like Tesla probably means something — maybe they’re just going to continue to be toys for the rich. And don’t hold your breath until the hydrogen infrastructure required for their new fuel-cell cars materializes.

In other words, unlike those of the other big emitters, America’s plan is going to cost us a bunch.

Speaking of money, that’s where there’s going to be trouble in Paris. Poor countries are demanding at least $100 billion every year from the developed world (read: us) so they can buy dodgy renewables, and to pay for the climate “damages” we have caused (hint: none). Last year they were rumbling about upping the tab to $150 billion. President Obama is desperate to come away with a finalized agreement so he can claim to have saved the world, even though Congress will never appropriate that money.

Still, it’s not likely that the Paris summit is going to agree to demand all that money. But in order to preserve an agreement, the first-world negotiators will promise that they will seriously work on a way to pay up in the next year. They’ll work on it until the first-class curtain closes on the return flight.

So, in summary, we get a climate agreement in Paris. It accomplishes nothing that wouldn’t have happened without it. The Third World won’t get its money, but, hey, in politics, a promise is a promise. If you like your climate agreement, you can keep your climate agreement.